Okay, we have some updates and changes. Working on projects like this is done on my own time. I don't use up company time or family time so I usually only get to work on these on Sundays.
As you can see in the picture below, a few things have changed as it progressed. There are now 4 midrange drivers and we have gone to an open baffle midbass arrangement. I know it's hard to visualize this speaker from the picture so I hope to have further updates and new pictures next weekend. By the way, sorry about the picture quality but I shot it with my cell phone as I forgot my camera today. Here's what we have.
The speaker is being designed in a module fashion. This will allow me to swap out the midrange/tweeter baffles with other designs as well as insert the baffles into sealed enclosures. see further details on this below the picture.
Okay, back to the arrangement: This speaker will need to be paired with subwoofers as it's low frequency cut off will be at only 70Hz. We basically have a large open baffle satellite speaker hear.
The midbass arrangement is using two 8" paper cone woofers with a high Qts. The woofers in the picture are only there for a visual effect as I would not use these cheap MCM poly cone woofers. As mentioned above, they will go down to only 70Hz. These 12 ohm woofers will present a 6 ohm load as wired and 92dB efficiency.
The midbass woofers will hand off to the midrange woofers at about 200Hz (further testing will have to be done before deciding).. These 4 woofers are paper cone pieces which also have a high Qts (shouldn't matter at these frequencies anyway) and a 4 ohm impedance. In the end, the midrange will show a 4 ohm load and 92.5dB efficiency.
The tweeter is an Accuton as I had a pair laying around. Big time overkill for this system but what the hell, why let them go to waste. I have not yet settled on the exact x-over frequency for the tweeter but it will probably be around 2,500Hz.
The modeling of the speaker is proving to be very positive but of course, it will be the ears and some measurements that tell the true story. From there, the fun part of tweaking begins
Module setup: As mentioned above, we are going this route to allow for a variety of midrange/tweeter arrangements. I already have another open baffle design that uses 4 pieces of 5" paper cone units, 1 Neo8 tweeter and a ribbon tweeter to provide air and extension above and beyond what Neo provides. This upper baffle is the same size as the one used in the speaker so interchanging will be very easy.
The other part of this design is that the baffles can be inserted into a sealed enclosure with it's interlocking set-up.
Well, that's it for this week.